Method of and apparatus for sealing thermometer tubes



Dec; 10, 1929. J, CHANEY 1,739,208

METHOD OF AND APPARATUS FOR SEALING THERMOMETER TUBES Filed Dec/l8. 1928 .H I I M 11 YEW" U 11/ U gjzwfiz AW ATTORNEYS Patented Dec. 10, 1929 UNITED STATES PATENT OFFICE JOHN GEANE'Y, OE SPBINGFIIEID, OHIO Application filed December 18, 1928. Serial No. 326,814.

This invention relates to a method of and apparatus for sealing thermometer tubes.

After the expansible liquid has been placed in the tube of the thermometer, it is the practice to seal the open end of the tube by subjecting it to a fusing heat and it has also been the practice to subject the tube immediately prior to the fusing operation, to the action of a cooling medium, such as an ice water bath, to reduce the temperature below that of room temperature, usually to a temperature of about 32 Fahrenheit. Heretofore these operations have been performed by hand, the

operator placing the tube in the ice water bath to reduce the temperature and then inserting the open end of the tube into the flame of a blow torch. Such operations required considerable time as the operator must handle each tube individually while undergoing these operations. One of the objects of the present invention is to enable a larger number of tubes to be sealed in a given length of time to materially reduce the cost of sealing.

- A further object of the invention is to provide a method and apparatus by which the operations of cooling and seallng may be simultaneously and more efi'ectively performed. 1

A further and more specific object of the invention is to provide a carrier for the tubes by which a series of tubes ma be conducted successively to a cooling me 'um and to a heat sealer; and finally be discharged into a suitable receptacle.

Further objects of the invention will ap pear from the accompanying description and claims.

In the accompanying drawings:

Fig. 6 is an enlarged diagrammatic view of a modification of Fig. 5.

Fig. 7 is a partial top plan view of a modification.

Fig. 1 is a side elevation, partly in section.

Fig. 8 is an enlarged sectional view on the line 8.8 of Fig. 7.

liquid therein, fusion. by heat of the upper end 6' to seal-the same being the final operation in thermometer manufacture at this stage. Y

A plurality of circumferential grooves 7 extend around the carrier 1, in which are placed belts or cords 8 and 9, preferably of some elastic material such as rubber, the belts 8 being in this case in the top and bottom grooves, while the belts 9 are in the inner grooves. A-pair of idler pulleys 10 mounted on a support 11, and a second pair of pulleys 12 on a support 13, are so disposed (as best shown in Fig. 3) to not only produce the desired tension on the belts 8 and 9, but also to provide for the placin of the tubes on the carrier and for the disc arge of the same therefrom after the sealing operation has been accomplished. It will be noticed in Fi 4 that the belts 8 are on the outside of the t ermometer tubes 6, and by the aidof the tension of the belts all tubes so placed are held firmly to the bottoms of the notches 4. Belts 9 are shown in this view as being at the bottom of the grooves in which they are placed, and by referring to Fig. 3 it is further noticed that at 14 I have arranged a convenient station at which to load the carrier 1' with tubes 6, since at this vantage point, the inclination of the carrier together with the fact that there is a noticeable convergence beween the belts 8 and 9 allows placement of the tubes in the notches between the belts 8 and 9. A disk 15' attachedto the carrier serves as a support for the bulb ends 6" of the tubes, and as the carrier is further rotated the belts 8 contact with i and hold the tubes to the bottoms of the notches 4. On the side opposite the station 14 is a delivery station 16 where by reason of the separation of the belts 8 and 9 (the belts 8 being passed around the pulleys 10, and the belts 9 around the pulleys 12) the thermometer tubes drop to a sloping chute 17, and into a suitable box 18.

At one point in the travel of the carrier the tubes are subjected to the heat of a plurality of torches or burners, four of these burners being employed in the present case as indicated at 19, 20, 21 and 22, in which gas or mixture of gases such as compressed free oxygen and natural gas is burned in the proper pro portions to produce a flame with a definite desired length of cone. The first three burners, considering the direction of travel of the carrier arefor the purposeiof preparing or gradually heating the ends of the tubes to a degree near that of the fusing point while the final burner, which has the heat of greatest intensity, performs tlie actual fusing and sealing of the tube. These burners are arranged in consecutive order adjacent to and in alignment with the path of the open ends of the thermometer tubes 6 and are spaced apart equal to the spacing of the tubes so that during each stoppage of the carrier, a tube will be beneath each burner, one tube being sealed and the proceeding tubes being heated in preparation for scaling.

As before mentioned, it is the practice to subject the tubes at the time of sealing to a cooling medium in order to contract the expansible liquid in the tube before sealing, this cooling medium being usually a bath of ice water which brings the temperature of the tube. to approximately 32 Fahrenheit. For that purpose there is located on the supporting table a tank 23 through which the carrier rotates, the bottom of the tank being inclined to a degree substantially equal to that of the inclination of the carrier. The tank is filled inthe present case with ice water, the level of which is indicated by the character 25 so that but a comparatively short length of tube is exposed to the flames, thus avoiding the danger of heating and expanding the expansible liquid in the bore of the tube, but at the same time leaving enough of the tube exposed to room temperature to protect the tubes against breakage when subjected to the temperatures of both the flame and water.

The direction of rotation of the carrier is shown by the arrow'in Fig. 3 and this carrier is rotated by the hand of the operator, the operator observing the tube under the last burner 19 in the series which performs the fusing operation so as to enable him to secure the proper fusing and sealing of the tube. The tubes are placed in the carrier at the station marked 14 and are discharged automatically at 16, the action of the flexible belts being to carry the tubes off of the supporting disk 15 at this point, the tubes then dropping by gravity from between the flexible belts into any suitable receptacle.

Besides the convenience and saving in time by mounting the tubes in series upon a carrier, other advantages are secured by this method and apparatus. The arrangement of the burners presents several advantages. First, by having a plurality of burners which gradually heat the ends of the tubes, asaving in time is efl'ected; second,'the gradual heating of the tubes in this manner prevents fire checks; third, the arran ement of the burners permits the flame to be projected on the extreme ends of the tubes which is much more effectivethan the old way of inserting the end of the tube laterally through the flame. It might be explained that the first burner 22 is regulated to give a. flame of comparatively low heating value, while the burners 21 and 20 are of increased intensity over the first burner and the final burner 19 is of such intensity that fusion takes place.

Another advantage in this arrangement is that it enables the tubes to be annealed slowly after fusing to prevent loss which is accomplished by reason of the fact that as the carrier rotates the tubes are carried gradually out of the cooling fluid in the tank 23 so that the tubes are exposed gradually to room temperature.

A frame 26 supported on the main frame 3 is fitted with glass sections 27 to protect the operator from the heat of the burners.

In Fig. .6 a modification of the method of producing a gradual heating is shown, in

which the series of burners 19' are placed at varying increasing distances from the ends 6 of the tubes, and are adjusted to show an approximately equal length of central cone, it being obvious that the fusing flame is that one which has its cone nearest the tube end.

In Figs. 7, 8 and 9 a. modification of the principle of rotatable carrier is shown, in which a carrier 1, similar in many respects to 1,,except having a series of openings 28, isprovided. This carrier 1' is mounted for rotation on a spindle (not shown) in an angular relation as is carrier 1, and in place of an attached flange 15, a plate 29, is secured to the main frame, (not shown) in parallel relation to the carrier 1. In this plate 29 I provide an opening 30 located at any convenient point near the upper side thereof so that when the belt 8' releases its grip on the tubes 31, in the present case a straight stem thermometer tube, the tube will drop through into 2. A method of sealing thermometer tubes consisting in positioning a series of tubes in uniformly spaced relation on a carrier, moving the carrier, subjecting the tubes to a cooling medium and also subjecting the tubes suc a carrier with the bulbs lowermost and the open end of the tubes uppermost, moving the carrier, subjecting the lower portion of the tubes to the action of a cooling medium by emersing the tubes therein, and subjecting the upper open ends of the tubes to the action of a fusing heat.

4. A method of sealing thermometer tubes consisting in arranging a series of tubes in upright position and uniformly spaced relation on a carrier with the bulbs lowermost and the open ends of the tubes uppermost, moving the carrier, subjecting the lower portion of the tubes to the action of a cooling medium by emersing the tubes therein, and subjecting the tubes successively to the action of a plurality of flames of different intensity during the travel of said tubes.

5. In an apparatus of the character described, a carrier, means for supporting a series of thermometer tubes on said carrier in successive order, a tank for a cooling medium through which said carrier moves, and a burner located in line with the path of travel of said tubes at the place where the tubes pass through, said tank.

6. In an apparatus of the character described, a carrier, means for supporting a series of thermometer tubes on said carrier in uniformly spacedrelation, a tank for a cooling medium through which said carrier moves, and a plurality of burners located in line with the path of travel of the exposed parts of said tubes where they pass through said tank, said burners being spaced equal to the spacing of said tubes.

7. In an apparatus of the character described, a rotatable circular carrier set at an inc ine, means for supporting thermometer tubes about said carrier in successive order, a tank for a cooling medium at the lowest point of travel of said carrier through which I said carrier passes, and a fusing burner also at the lowest point of travel of said carrier.

8. In an apparatus of the character described, a rotatable circular carrier set at an incline, means for supporting thermometer tubes about said carrier in uniformly spaced relation, a tank or cooling medium at the lowest point of travel of said carrier through which said carrier passes, and a series of burners at the lowest point of the travel of said carrier in line with the path of travel of the exposed parts of said tubes, said burners being in spaced relation conforming to the spacing of said tubes.

9. In an apparatus of the character described, an inclined rotatable carrier, means for supporting a series of thermometer tubes about said carrier with the bulbs thereof lowermost and open ends thereof uppermost, means located in the path of the tubes for reducing the temperature of the same, and means also located in line with the path of the tubes for sealing the same.

10. In an apparatus of the character described, an inclined rotatable carrier, means for supporting a series of thermometer tubes about said carrier with the bulbs thereof lowermost and open ends thereof uppermost,

means located in the path of the tubes for reducing the temperature of the same, means also located in line with the path of the tubes for sealing the same, and meanswhereby the tubes are automatically discharged from said carrier.

11. In an apparatus of the character described, a disk-like rotatable inclined carrier, equally-spaced pockets about the periphery of said carrier, said carrier having a floor beneath said pockets to support said tubes, a plurality of flexible bands arranged about said carrier in contact with said tubes to prevent lateral displacement of said tubes, and a plurality of additional bands about said carrier cooperating with said first mentioned bands to remove said tubes from said carrier at one point in the rotation thereof.

12. In an apparatus of the character described, a disk-like rotatable inclined carrier, equally-spaced pockets about the periphery of said carrier, said carrier having a floor beneath said pockets to support said tubes, a

plurality of flexible bands arranged about said carrier in contact with said tubes to prevent lateral displacement of said tubes, a plurality of additional bands to remove said tubes from said carrier at one point in the rotation thereof, and an idler pulley for each band located at the side of said carrier disk at the point of discharge.

In testimony whereof, I have hereunto set my hand this 27th day of November, 1928.

JOHN L. CHANEY 

